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Heliocentric radius of the cosmic-ray modulation boundary. Progress report

Technical Report ·
OSTI ID:5111060
A semi-empirical analysis is made of our extensive body of observed cosmic-ray intensity data from Pioneers 10 and 11 and related spectral information from other sources in order to infer the radius R of the modulation region surrounding the sun. During the period 1972-1985, the inferred values of R vary with the time systematically and in manner generally similar to that of sunspot numbers. The range of values of R is from 42 AU at the time of minimum solar activity (about 1976) to 88 Au about 1.5 yr following the time of maximum solar activity (about 1980). A specific, testable prediction is that Pioneer 10 will cross the modulation boundary in 1988 and will remain in its vicinity for several years thereafter.
Research Organization:
Iowa Univ., Iowa City (USA). Dept. of Physics and Astronomy
OSTI ID:
5111060
Report Number(s):
AD-A-169692/1/XAB
Country of Publication:
United States
Language:
English